Abstract
A procedure was developed for the analysis of dazomet residues in tomato, cucumber and cabbage employing high performance liquid chromatography (HPLC). The crops were homogenized with silver diethyldithiocarbamate (DDTC-Ag) and extracted with dichloromethane. The addition of DDTC-Ag was necessary for all samples to obtain a good recovery of dazomet. The extract was concentrated and cleaned up using a Florisil column. The concentrated eluate was analyzed by HPLC employing a Nucreosil 5CN column and a 2, 2, 4-trimethylpentane-ethyl acetate solvent system. Dazomet was detected by ultraviolet absorption (285nm) and 0.5ng per injection was detectable. Recoveries of spiked samples were 78-95% at 0.05ppm level and 83-88% at 0.2ppm level with a lower limit of detection of 0.005ppm (tomato and cucumber) and 0.01ppm (cabbage). This HPLC method was more specific for dazomet than the conventional colorimetric method.
